Oracle allows employees to elect dual coverage where the dependent is also an employee

Summary:

Oracle allows employees to elect dual coverage where the dependent is also an employee, This is problematic because carriers do not allow dual coverage except for life insurance. Can this be fixed for all coverage's except life insurance?
High priority due to employees potentially paying for benefits that will not pay because of ineligibility.
the plans that prohibit dual coverage are PPO Medical Plan, HRA Medical Plan, HSA Medical Plan, Copay Medical Plan, Delta Plan, Vision Plan, Accident Care, Hospital Indemnity, and Critical Illness.

The plans that allow dual coverage are Basic Life, AD&D Life, Dependent Life, Supplemental Employee Life, Supplemental Spouse Life, and Supplemental Child Life.